Method and apparatus for storing gaseous materials in the liquid phase



. l v 2,328,647 s FOR sToRING GAsEoUs MATERIAL sept. 7, 1943. J. o. JACISON METHOD AND APPARATU IN THE LIQUID PHASE Filed Aug. 6, 1941 Y- BY gli??- @t ATTORNEYS 2,328,647 MATERIAL Sept. 7, 1943.

J. O. JACKSON ATUS FOR STORING GASEOUS l METHOD AND APPAR 1N THE LIQUID PHASE Filed Aug. 6, 1941 2 Sheets-Sheet 2 lNvEN 0R ML ATTORNEYS mer methods.

Patented Sept. 7, 1943 a,-32s,s47 METHOD AND APPARATUS Foa s'romNG GASEOUS MATERIALS PHASE IN THE LIQUID James 0. Jackson, Grafton, Pa. Application August s, 1941, serial No. 405,648

(ci. ca -122) 11 Claims.

This invention relates to a method and apparatus for the storage of normally gaseous materials in the liquid phase and more particularly to the working or live storage thereof under conditions where the amounts of such'materials in storage vary from time to time by the addition and withdrawal of portions as contrasted with .so-called dead storage where the materials remain in storage for a considerable length of time without addition to or withdrawal from the total volume being stored.

In the working storage of large volumes of gaseous materials such as natural gas, the practice has been to store large quantities thereof by pumping the same into containers of various kinds. Gases may be pumped into gas holders of the telescopic or rigid loaded piston type and in either case the degree of compession is very small due to the nature of the container so that to store extremely large quantities of gases, extremely large and costly containers must be provided. Gasesmay be compressed to a greater degree in steel or other containers such as spherical containers designed for high pressure, or they may be compressed into old exhausted gas wells in the ground. In the storage of large quantities of gas, however, the cost of the containers becomes prohibitive for if the pressure is low a great number of them are required while if the pressure is high the cost of the smaller number of containers is proportionately increased due to the increased pressure. In the case of ground storage the pressure required to place the gases back into their natural pockets and to displace the earth waters filling themis excessive, thus causing a very high pumping cost.

Gases have been stored in the liquid phase,l

only a few days duration and betweenl them it is usually possible to restore gas used during the peak periods.

One of the objects of my present invention is to provide a method and apparatus for the liquefaction, storage and regasification of gas under working or llive storage conditions and without the necessity of performing a large amount of expensive mechanical work in so doing.

Another object of my invention resides in providing an apparatus or system by means of which gas may be stored and increased or decreased in volume or amount at will and without the expense ordinarily attached to such operations.

A further object of the invention resides in the provision of a method and apparatus by means of which liquefied gas may be regasled through heat exchange of another gaseous material which yother and further matters as will either be understood by those skilled in this art or explained in the following specication.

In the accompanying drawings in which I have illustrated a. preferred form of apparatus responding to my present invention and in which like numerals designate corresponding parts:

that is, by liquefying them and transferring the liquid to suitably insulated containers, then when the gas is wanted for use it may be regasied or vaporized by the application of heat to the liquefled gas. This method of storing gas has made possible the storage of very much larger quantities of gas in a given space than any of the for- However, it has had the disadvantage that a large amount of mechanical power involving high operating costs has had to be provided for liquefaction and subsequentl regasiflcation purposes. This has been particularly true when all or a portion of the contents of the stored gas may be used and replaced several times each year as is customarily the case when domestic gas is stored at off-peak periods to provide for peak demand during extreme winter weather cold spells. etc. for such cold spells are usually of Fig. 1 is a vertical medial section taken through my new apparatus; and

Fig. 2 is a horizontal sectional view, partly in plan, taken on the line III-II of Fig. 1 and in the direction of the arrow thereof.

Referring now to the drawings, it will be observed that 20 is a hollow spherical liquid air storage tank constructed of suitable alloy steel sheets fastened together as by welding and supported by insulating blocks 2| of corkboard or the like. Blocks 2| extend slightly more than 45 around the lower `portion of tank 20 on each side of the vertical center line and are themselves supported by steel tank shell 22 concentric to 'tank 20 and which may be -made of ordinary sheet steel fastened as by welding, riveting or the like. Outer shell 22 is supported at about its vertical midpoint by steel columns 23 which rest on concrete foundations 24 embedded in the earth. Completely lling the space between tank 20 and spaced shell 22, not occupied'-by 2i, is

heat-insulating material 25 which may be of a granular nature such as granulated cork, this 'material being preferred for the non-load bearing portion of the insulation because of its lower cost. A substantially cylindrical extension 26 projects upwardly from the top of shell 22 and is also lled with granular cork or the like. Vent pipe 21, which is sealed to 26 by stufng box 28, extends through extension 26 and the cork therein and communicates with the interior of tank 26. Pipe 21 terminates at its upper extremity in a manifold 29 which is closed at one end by the rupture disc 36 and at the other end by a pressure-vacuum control valve 3l.

Inlet and outlet pipe 32 is connected into tank 28 at the lowest point of such tank and is surrounded by pipe insulation 33 which is preferably of the molded cork type well cemented and covered. Pipe 32 is valved at 40, the valve stem projecting through the covering 33 for insulation 32, as shown.

26a is a sheet metal spherical shell for the storage of liquid gas and is identical in construction with shell or tank 20. The associated parts are likewise similar to those already described in connection with tank 20 as will be denoted by the use of corresponding numerals but followed by an a. Vent pipe 21a is, however, additionally provided with a horizontal branch pipe 34 yalved at its distal end as at 35.

Located suitably between liquid air tank 20 and liquid gas tank 20a is a vertical heat exchanger or column extending approximately from the ground to the elevation of the tops of the liquid air and the liquid gas tanks and having a sheet metal inner shell 36 and a sheet metal outer shell 31, the space therebetween being iilled with granulated insulating material 25e. Serving as a support for 36 and 31 is a metal base 38 which is positioned on the concrete foundation 39. Pipe 32 connects with the interior of shell 36 near its lower end and pipe 32a, which passes through shell 36, connects with the interior of tube 42 near its bottom. Tube 42 is provided with a central rod 4| which carries and acts as a support for the baiiles 54 which are staggered with respect to bailles 53 extending inwardly from tube 42. Baiiies 52 extend outwardly from tube 42 and are staggered relative to the baflies I which project inwardly from shell 36. The lower end of pipe 44 extends into the top of tube 42 and is held in position by a nange arrangement 43. A stuffing box arrangement 45 seals pipe 44 to shell 36. An extension 46 of pipe 44 is sealed at one end to stufling box 45 and another stufling box or flange assembly 41 seals the upper end of pipe 46 to shell 31. A suitable valve or fitting 48 is provided on the upper end of pipe 46 for a purpose to be described. A branch pipe 49, having a valve 5U at its outer end, extends through shell- 31 and communicates with the interior of shell 36. Pipes 46 and 44 constitute gas inlet means and branch pipe 49 constitutes an air inlet means.

In the operation of my device the liquid gas tank 20a is first lled to its normal working level, which makes it approximately -full but leavespressure of about 10 pounds per square inch and serves to positively vent the tank contents in case of failure of valve 3l a to operate. Because of a continual infiltration of heat through insulation 21a and 25a the liquid gas is being constantly vaporized and this vapor passes off through vent pipe 21a and, normally, through pressure-vacuum relief valve 3Ia. When it is desired to remove some gas from storage, air is pumped through pipe 49 under enough pressure to cause it to liquefy and flow into tank 20. Valve 46a is then opened and valve 48 slightly opened. This will allow the liquid gas to flow through pipe 32a into tube 42 where it will assume some level which may be regulated by the extent of the opening of valve 48. The heat from the incoming air in shell 36 is absorbed lby the liquid gas and as the latter is volatilized it rises, passing around baffles 53 and 54 and finally out through 44 and 46. The total heat exchanging surface is suflicient to transfer the heat from the incoming air to the liquid `gas so that the temsuflicient free space to allow continuous venting -of any generated gas without causing-liquid to foam through vent pipe 21a. Valve 40a is normally closed and pressure and vacuum relief valve 3| a is set to limit the safe operating pressure and vacuum. v,I prefer to use a setting of 5 pounds per square inch pressure and about l ounce per square inch-vacuum.

Rupture disc 30a is designed to break at a perature of the gas leaving valve 48 is only slightly below that of the air entering through valve 50. It is thus seen that as air is introduced through valved pipe 49, it liquees, gradually filling the liquid air tank 20, while the liquid gas is evaporated, causing tank 20a to empty gradually.

When it is desired to put more gas in storage, valves 40 and 40a are opened, valve 50 partially opened and gas is introduced through valve 48 at a pressure of only a few pounds per square inch or just enough to move the required volume into the liquid gas tank 20a. The liquid air rises in shell 36, and, through the shell of tube 42 and the baffles or ns shown cools the incoming gas, causing it to become liquid and to flow into the liquid gas tank 20a. At the same time the liquid air in shell 36 is vaporized and, by proper adjustment of valve 50, can be so regulated as to leave through 46 at a pressurek only slightly below that of the gas entering via valve 48. If this operationis continued the gas tank may be completely lled, with the result that the liquid air tank will be substantially emptied.

It is thus seen that a large quantity of gas may be liquefied and placed in storage or may be regasied and taken from storage with the expenditure of only a relatively small amount of energy, that is, only enough to overcome the internal friction and to cause the required volume of gaseous air or gas to flow into and out of the system.

Of course, the temperatures at which the air and the gases liquefy must be compatible although they need not be identical. For example, air liquees at a critical temperature of approximately 221 below zero Fahrenheit and at an absolute pressure of 547 pounds per square inch while natural gas or methane liquees at a critical temperature of 117 Fahrenheit below zero at a pressure of about 673 pounds per square inch. However, the temperature of liquid methane at a pressure of one atmosphere is approximately 260 below zero Fahrenheit while the vapor pressure of liquid air at this temperature is approximately 175 pounds per square inch absolute and the temperature of liquid air is approximately heit below zero when the gas is being withdrawn. Since the temperature of the liquid gas is 260 below zero Fahrenheit the air must be compressed to a pressure of about 175 pounds per square inch yor more in order for it to liquefy.

These pressures may be regulated either manually or automatically by manipulation of valves 40 and 40a. v

Since the total heat required to be removed from l pound of methane gas at normal temperature in order to cause it to liquefy is approximately twice that required to be removed from 1 pound of air, it follows that provision for storage of approximately twice the Weight of air as compared with the desired weight of gas must be provided.

There is a continual vaporization in both the liquid air and the liquid gas because of the infiltration of heat through the insulation. This may be offset by the addition periodically of small quantities of liquid air into the liquid air container.

Gas which normally evaporates from the liquid gas container due to the inltration of heat through the insulation may be conducted by valved branch pipe 34 to a suitable container or to the gas mains, or may be returned through valve 48 and liquefied in the usual manner.

The foregoing is intended as illustrative and not as limitative and, without departing from the scope or principles hereof, I may resort to various modifications, additions, omissions and substitutions. The invention is rather dened by the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. Apparatus for the storage of one kind of al gaseous material in its liquid phase and for regasifying the said stored liquefied gas by means of a second kind of gaseous material which comprises an insulated container for each such material, a heat exchanger for exchanging heat between the gaseous and liquid materials in such contaners and for causing the initially gaseous material to become liquefied Iand the initially liquid material to become gasied.

2. Apparatus for the storage of one kind of a gaseous material in its liquid phase and for regasifying the said stored liquefied gas by means of a second kind of gaseous material which comprises a heat exchanger for exchanging heat between such gaseous and liquid materials and for causing the initially gaseous material to become liquefied and the initially liquid material to beacts through said heat exchange unit and said heat4 exchange unit including an outer shell, a

come gasified, and means for reversing the liquel fyin'g and gasifying conditions to restore the original phases of the materials.

3. Apparatus for the liquefaction and regasication of a gaseous substance which comprises an insulated container for the storage of the gaseous substance in liquid phase and an insulated container for the storage of another gaseous substance also in liquid phase and a. heat exchanger in operative relationship with said containers, the construction and arrangement being such as to remove the heat from the rst gaseous material causing it to liquefy by the vaporization of the liqueed second gaseous material.

4. An apparatus of the character described which comprises a heat exchange unit, a pair of insulated tanks operatively associated with said e heat exchange unit, means for introducing liqueed gas into one of said tanks and means for second shell within and spaced from said outer shell, heat insulation lling the space between such shells, a tubular member within and spaced from said second shell, means for effecting communication between said liquid gas tank and the interior of said tubular member and means for effecting communication between the vother tank and the interior of said second shell.

6. An apparatus of the character described which comprises a heat exchange unit, a pair of insulated tanks operatively associated with said heat exchange unit, means for introducing lique. fled gas into one of said tanks and means for withdrawing regasiiied gas from that same tank, said liquefaction and regasication being effected through gasiilcation and liquefaction of air which acts through said heat exchange unit and said heat exchange unit including an outer'shell, a second shell within and spaced from said outer shell, heat insulation filling the space between such shells, a tubular mem-ber within and spaced from said second shell, means for effecting communication between said liquid gas tank and the interior of said tubular member and means for effecting communication between the other tank and the interior of said second shell, a system of staggered bailies being provided between the second shell and the tubular member and interlorly of the said tubular member.

7. Apparatus for storing a gaseous material in its liquid phase and for regasifying the same by means of a second gaseous material which comprises a pair of spaced containers each of which is adapted to receive and store a liquefied gas and each of which is insulated against the infiltration of heat thereinto and an insulated heat exchange tower located in the space between said containers and operatively connected thereto.

8. Apparatus for storing a gaseous material in its liquid phase and for regasifying the same by means of a second gaseous material which comprises a pair of spaced containers each of which is adapted to receive and store a liquefied gas and each of which is insulated against the inltration of heat thereinto and an insulated heat exchange tower located in the space between said containers and operatively connected thereto, each such container being in the form of a fluidtight metallic sphere composed of a material reis adapted to receive and store a liqueed gas and each of which is insulated against the infiltration of heat thereinto and an insulated heat exchange tower located in the space between said containers and operatively connected thereto, said heat exchange tower being provided internally with a. plurality of sets of staggered baffles so constructed and arranged as to secure a substantially complete exchange of heat between nids without undue inltration of heat into the exchanger.

10. Apparatus for storing a gaseous material in its liquid phase and for regasifying the same by means of a second gaseous material, which comprises a pair of spaced substantially spherical containers, a substantially similarly shaped metallic shell disposed around and spaced from each such container, molded cork insulating blocks disposed in the bottom portion of each such shell and arranged to support substantially the entire weight of the container located therein, granular cork iilling the remaining space between each container and its shell, means for introducing iiuid into and removing fluid from each such ccntainer and meansl for venting each such container when under excess pressure conditions.

11. Apparatus for storing a gaseous material in its liquid phase and for regasifying the same by means of a second gaseous material, which comprises a pair of substantially spherical containers spaced one from another, a heat exchange tower disposed between such containers and operatively connected to each ofthe same; said tower including a pair of spaced inner and outer metallic shells with granular heat insulating material filling the space therebetween; the inner shell being in communication with one such container, a central tube disposed within the inner of such shells and being in communication with the other container, and a system of battles disposed both internally and externally of said central tube.

JAMES O. JACKSON. 

